Process and machine for manufacturing tubes



E. PUMP Jan; 2, 1934;

PROCESS AND MACHINE FOR MANUFACTURING TUBES Filed Oct. 22, 1929 Patented Jan. 2, 1934 PROCESS AND Mscnmn roa immac- 'rumncyrnans Ernst Pump, Hamburg,'Germauy Application October 22, 1929, Serial No. 401,598,.

and in Germany October 23, 1928 3 Claims. (o1. 153-2)- I This invention relates to a process and machine for manufacturing tubes such as are used for winding ribbon, adhesive tape, insulating tapes and the like and is remarkable in that 6 the tubes are made in a single up and down movement from a continuous sheet metal strip in such a manner that during downward movement the cut metal strip is pressed over a mandrel to form tubes, the ends of which are bent over by means of counter runningbeading tools using cam races and at the termination of the downward, movement are embossed with ever, do not relate to the manufacture of tubes,-

the ends of which are bent over but only for making quite plain tubes. An objection to the known machine is that a number of consecutive operations must be can-led out in order to obtain the desired shape. As compared therewith the invention is remarkable for the fact that the simultaneous bending or beading of the ends of the tube is efiected at the same time as the other.

operations, and that for the whole operation only a single ram is used so that for this arrangement any other machine, for example, eccentric or crank press, can be used. Thus a tool mechanism is produced which can be fitted to any other machine, and the construction of which is such that at each stroke movement of the machine a suitable metal strip is fed, cut and bent to the shape of a sleeve or tube, bent in or beaded at the ends, stamped and ejected as a finished product.

A form of construction of the arrangement for carrying out the process is illustrated by way of example in the accompanying drawing, in which:-

Fig. 1 is a cross section through the tool. Fig. 2 is a section on line 2-2 of Fig.- 1. Fig. 3 is a section on line 8-3 of Fig. 4. .Fig. 4 is a section on line 44 of Fig. 1.

Fig. 5 shows in cross section the finished tube. According to the example chosen tubes of the kind illustrated in Fig. 5 having at their ends beads a and provided in their circumference with stampings b are to be madein a single stroke movement of an -eccentric press. c is the upper part and d the lower part of the press. 0n the -further downward movement of the ram the springs h.

upper part c a plate e is arranged which is held above a counter plate g by means of springs f. The metal strip i is fed by an automatic feeding device in known manner between the two plates e and g. These two plates serve for preliminarily bending the strip which is'then fed forward and arrives over the female die It. This female die is also resiliently mounted on the lower part d and a male die I is arranged above the female die k which is also resiliently mounted in regard to the upper part 0. According to Fig. la stamp m is arranged in front of the female die and male die, as shown in Figs. 3 and 4, on which a core or mandrel m1 according to the actual form of the tube is fastened. This mandrel as hereinafter described presses the sheet metal band i into the matrixk. On each side-of the mandrel m1, beading tools in and n: are arranged which carry out the beading in the manner described. The ejecting device consists of a double armed 76 lever o pivotally mounted on a pin p on the upper part c. One arm of the lever carries an ejecting arrangement 01 whereas the other arm is guided in a cam groove connected with the lower part d.

The arrangement will be more clearly under- 80 stood through .the description of the process which is as follows:

When the upper part c is in inoperative position, the preliminary bending plates e and a are held apart by their springs I so that the 8 strip i can be fed between these plates. -When, however, the part c commences to move downward the cheeks n and r: hingedly connected to the upper part c as shown in Fig. 2 press the plate 0 tightLv against the plate a by means of their projections s1 and 8:. The material i is thereby bent in the desired manner. During the descending movement of the ram c the pressed together plates e and a are thereafter moved down until a blade'ti connected with the plate c cooperates in shear-like manner with a rigid blade is fastened to the lower part d. Thus a part of the sheet metal band i is cut on. On the cheeks 1-1 and r: strike against guide curves I 0 vi'and m, are swivelled outwards and their projections slide on the pressure plate 0.

The section of band i which has beencut off, then again travels upward under the pressure of the During the further movement of the rain the mandrel'mi connected with the pressure bolt m comes in contact with the cut-off section of the sheet metal band and presses it into the half of v the female die situated thereunder and which is also under pressure. The band is bent approximately in U-shape after which the piston is held back with its mandrel until the male die lhas been pressed on the female die I: and thereby the rolling of the tube is finished. Upon the further movement of the ram 0 it carries down the male die 1 and female die I: together with the rolled sheet metal tube and the mandrel m1 situated therein. Two beading tools 111 and m movably mounted at both ends exactly in the plane of the central axis of the tube are moved in opposite direction to the tube by running on the guides w and 1m, whereby they are positively moved towards the tube. Thus a bead is produced on both erids of the tube. At the extreme movement of the ram the female die it reaches a shaping stamp m fastened to the lower part d which passes through the female die and effects the shape stamping 2: shown in Fig. 5. At this point the ram has finished its movement in downward direction and then commences its upward movement. The finished tube is then as shown in Fig. 4 stripped off the mandrel ml in the following manner: the lever o is pivotally mounted on a bolt p on the upper part c. The rotation is eflected in that the lever arm 0 slides in the cam groove q so that on the downward movement of the ram the lever o is swung to the side. During the upward movement of the ram the stripping device 0 effects a return movement in the direction 1! and thereby strips the tube oi! the mandrel m1. In this manner a tube according to Fig. 5 is finished in a single working operation. Thus for example during a single rotation of an eccentric press a finished tube according to Fig. 5 will be turned out. An important fact is also that the necessary piece of material is cut oil and finish worked without any waste.

I claim:---- 7 -1-. A process for manufacturing tubes, reels, and the like from sheet metal in band form, consisting in bending up the front edge of the sheet metal fed in the form of a band, in cutting a length of material from said band at the same time bending up the front edge of the band for the nextfollowing length, in bending the cut length into the shape of a tube and in beading the ends of said tube all operations being effected automatically during a single reciprocation of a ram.

2. A machine for manufacturing tubes, reels, and the. like from sheet metal in band form, comprising in combination a press table, a dleplate resiliently mounted on said table, a ram vertically reciprocatable above said table, a counter die-plate resiliently mounted on the under side of said ram adapted to co-act with said die-plate to bend up the end of the sheet metal band, a female die resiliently mounted on said table adjacent said first mentioned dieplate, a male die resiliently mounted on said ram adjacent said counter die-plate, a knife on said ram between said counter die-plate and said male die adapted to cut a section of the required length from said band, a mandrel carried by said ram and projecting between said female die and said patrix adaptedto co-operate with same female dies to shape said band into the form of a tube, a pair of beading tools oscillatable on said ram, one at each end of said mandrel, means for pressing said tools against the ends of the female die and said male die, a lever oscillatably mounted on said ram, an ejecting device on one arm on said lever, and a cam on said table adapted to actuate said lever to cause said ejecting device to strip the tube from said mandrel and ejectsame, so that during each reciprocating motion of the said ram a section of material is cut from the band shaped, beaded, and ejected as a finished tube, and, at the same time, the edge of the metal band is preliminarily bent up for the next following tube.

3. A machine as specified in claim 2, comprising in combination with the ram and the lower shaping die, a stamp in said die adapted to stamp the side wall of the tube at the end of the downward movement of said ram.

ERNST PUMP. 

